<<

ogy iol : Cu ys r h re P n t

& R Anatomy & Physiology: Current

y e s

m

e

o

a

t Rohilla et al., Anat Physiol 2018, 8:1

r

a

c

n h A Research DOI: 10.4172/2161-0940.1000293 ISSN: 2161-0940

Case Report Open Access

Extensor Digitorum Brevis Manus: A Rare Case Report Aarti Rohilla, Monika Rathee, Kamal Singh* and Suresh Kanta Rathee Department of Anatomy, Pandit Bhagwat Dayal Sharma Post Graduate Institute of Medical Sciences, India *Corresponding author: Kamal Singh, Department of Anatomy, Pandit Bhagwat Dayal Sharma Post Graduate Institute of Medical Sciences, India, Tel: +91-9812531007; E-mail: [email protected] Received Date: February 05, 2018; Accepted Date: February 20, 2018; Published Date: February 27, 2018 Copyright: © 2018 Aarti Rohilla, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

Abstract

The awareness of variant muscle bellies and in the is of great interest to the hand surgeons. The knowledge of these muscles is useful for both in teaching human anatomy and in clinical practice; while performing the hand surgeries and transplants. In routine dissection an accessory muscle. i.e. extensor digitorum brevis manus was observed that was attached on the proximal phalanx of middle .

Keywords: Hand; Dorsum; Accessory muscles Case Report A variant muscle was found on the dorsal surface of hand of a 65- Introduction year-old Indian female cadaver during routine dissections for The dorsum of hand contains only the tendons of the extensor undergraduate medical students in the Anatomy Department, PGIMS, muscles of the and devoid of muscle bellies. The tendons Rohtak. This variant muscle is extensor digitorum brevis manus which present on dorsal surface are- Extensor pollicis longus, Extensor proximally attached deep to the extensor retinaculum on lower end of indicis, Extensor digitorum and Extensor digiti minimi. However, , radiocarpal ligament and the joint capsule and distally it muscles and tendons with anatomic variations in dorsum musculature is attached on base of the proximal phalanx of middle finger on the of hand have been reported in numerous publications: they are the medial side. It is supplied by posterior interosseous and by a extensor digitorum brevis manus (EDBM, reported in 1-3% cases) [1], branch of posterior interosseous (Figure 1). accessory abductor digiti minimi (present in 24% of cases), extensor medii proprius (present in 0.8-10.4% of cases) [2]. These muscles may be difficult to diagnose and easily mistaken for ganglion, synovial tumour or soft tissue tumours.

Figure 1: Showing the origin and insertion of extensor digitorum brevis manus muscle (EDBM). Other Muscles shown are Extensor Indicis (EI), Extensor Digitorum (ED) and Extensor Digiti Minimi (EDM).

Anat Physiol, an open access journal Volume 8 • Issue 1 • 293 ISSN:2161-0940 Citation: Aarti Rohilla, Monika Rathee, Kamal Singh, Suresh Kanta Rathee (2018) Extensor Digitorum Brevis Manus: A Rare Case Report. Anat Physiol 8: 293. doi:10.4172/2161-0940.1000293

Page 2 of 2

Discussion for a ganglion or other tumor by clinicians [4]. It can be treated surgically by resection of EDBM or by releasing extensor retinaculum. The extensor digitorum brevis manus is an anomalous muscle that Thus, the knowledge of this dorsal muscle variant is critical for takes origin from the lower end of radius, radiocarpal ligament, or the surgeons [12]. lower end of [3]. The tendon inserts into the or, less commonly, into the middle finger. Another author describes its origin from the lower end of radius, radiocarpal ligament and the capsule of References wrist joint, and insertion into either the extensor expension of the 1. Teh J, Whiteley G (2007) MRI of soft tissue masses of the hand and wrist. second, third or both the second and the third digit [4]. Br J Radiol 80: 47-63. Tan ST, Smith PJ (1999) Anomalous extensor : a Paraskevas found the EDBM on the dorsal surface of the right- 2. review. J Hand Surg Am 24: 449-455. hand. He noted the origin of this variant muscle deep to the extensor 3. Doyle JR, Botte MJ (2003) Anomalies and Variations: Extensor retinaculum from the wrist joint capsule and insertion into the medial Digitorum Communis. In: Surgical Anatomy of the Hand and Upper side of the base of the proximal phalanx of the index finger [5]. Extremity. (1st edn), Lippincott Williams & Wilkins: Philadelphia P: 139. The first description of this anomalous muscle is given by Albinus in 4. Ouellette H, Thomas BJ, Torriani M (2003) Using dynamic sonography to 1734 and Nakano found approximately 295 cases in his extensive diagnose extensor digitorum brevis manus. Am J Roentgenol 181: 1224-1226. bibliographic review [6]. Bunnel [7] and Souter [8] reported that EDBM represents a failure of the proximal migration of ulna-carpal 5. Paraskevas G, Papaziogas B, Spanidou S, Papadopoulos A (2002) Unusual variation of the extensor digitorum brevis manus: a case report. Eur J elements of forearm muscle mass in humans, but in amphibians this Orth Surg & Trauma 12: 158-160. muscle controls the digits. Stith and Browne described that this muscle 6. Albinus BS (2008) Annotationes academicarum. Netherlands p: 28. can be present with two bellies of different sizes [9]. Rodriguez- Bunnell S (1956) Surgery of the hand. London: Pitman Medical 3rd edn. Niedenführ reported 3 cases of EDBM out of 128 cadavers studied 7. P: 4. [10]. 8. Souter WA (1966) The extensor digitorum brevis manus. Br J Surg 53: AV Ranade studied 72 cadavers out of which EDBM was found in 821-823. 3 cadavers. They defined its origin from the lower end of the radius, 9. Stith JS, Browne PA (1979) Extensor digitorum brevis manus: a case radiocarpal ligament, and wrist joint capsule and inserted on the report and a review. Hand 11: 217-223. tendon of the extensor digiti medii proprius [11]. 10. Niedenführ M, Vazquez T, Golano P, Parkin I, Sanudo JR (2002) Extensor digitorum brevis manus: anatomical, radiological and clinical relevance. A review. Clin Anat 15: 286-292. Conclusion 11. Ranade AV, Rai R, Prabhu LV, Rajanigandha V, Prakash, et al. (2008) The extensor digitorum brevis manus located on the dorsal surface Incidence of extensor digitorum brevis manus muscle. Hand 3: 320-323. of the hand is asymptomatic but the symptoms like pain and swelling 12. Komiyama M, Nwe TM, Toyota N, Shimada Y (1999) Variations of the and tendon. J Hand Surg 24: 575-578. may appear due to repeated work of hand or heavy manual work. It can cause local discomfort or tendon dysfunction. It can be mistaken

Anat Physiol, an open access journal Volume 8 • Issue 1 • 293 ISSN:2161-0940